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See detailOptimization of the Return Link Carrier Planning for a Constant Coding and Modulation Satellite Network
Lacoste, Clément UL; Maturo, Nicola UL; Chatzinotas, Symeon UL et al

in Frontiers in Communications and Networks (2021), 2

In this paper, we propose an approach to optimize the frequency plan and associated bandwidth allocation in the return link of a broadband satellite network, by exploring several design techniques for ... [more ▼]

In this paper, we propose an approach to optimize the frequency plan and associated bandwidth allocation in the return link of a broadband satellite network, by exploring several design techniques for carrier allocation plans. Since bandwidth is a limited resource in satellite telecommunications, the minimization of bandwidth usage is a core issue that satellite communication service providers must solve, in particular for networks using a constant coding and modulation plan, which lacks the flexibility found in newer satellite communication products and can be subject to hardware constraints. This problematic led us to raise the following question: how can the long term bandwidth requirement of the network be minimized, given a set of ground terminals, of Modulations and Codings, and of discrete bandwidths. In this document we formally define the long-term carrier allocation problem and analyze current practical solutions. We subsequently investigate two other potential solutions, found to be more bandwidth-efficient: one based on heuristics and another based on integer linear programming. Finally, we look at the impact of several parameters on the performance of those three methods. Overall we observed marginal reductions in bandwidth, however significant gains were reached for networks with small return links with low committed information rate, a case in which some constant coding and modulation networks could fall. We concluded that those networks could benefit from our methods and see a significant reduction in bandwidth, and subsequently operational costs, at low implementation costs. [less ▲]

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See detailLes réseaux socionumériques : un mirage pour l’érudition
Lukasik, Stéphanie UL

in Hermès la revue (2021), 87

Digital Social Networks : A Mirage for Scholarship Digital social networks constitute a mirage for scholarship. While a necessary condition of scholarly research is the availability of a diverse range of ... [more ▼]

Digital Social Networks : A Mirage for Scholarship Digital social networks constitute a mirage for scholarship. While a necessary condition of scholarly research is the availability of a diverse range of information, using digital social networks to gain access to sources can limit informational plurality. As a result of their homophilous functioning, there is not much interplay of content on social media. In concretizing, on a large scale, both the two-step flow of communication model and the figure of the opinion leader, online social media are platforms within which users-receivers get their information from other members of their own social networks. Receiving information through an opinion leader changes how it is grasped. Without the different facets of a piece of information, it is difficult to attain a scholarly perspective, because this requires in-depth study and a comparison of sources. Only the personal reconstruction of a variety of sources can restore the heterogeneity that scholarship demands. [less ▲]

See detailLa reformulation de la figure du leader d’opinion au prisme de la réception de l’information des jeunes adultes via les réseaux socionumériques
Lukasik, Stéphanie UL

Doctoral thesis (2021)

Social-digital networks are linked to the user-receiver activity theorized by the Columbia school. In their model of two-step flow of communication, the Columbia researchers focused on non-digital social ... [more ▼]

Social-digital networks are linked to the user-receiver activity theorized by the Columbia school. In their model of two-step flow of communication, the Columbia researchers focused on non-digital social networks. The link between the media system and the social system that the Columbia school anticipated seems all the more relevant with the collect of information via social networks. Henceforth, the media must reckon with social networks and consequently with users-receivers. By sharing information, each user-receiver can become a short-term opinion leader by influencing their secondary groups and by arousing gratifications. The one-off act of sharing materializes this new filter which symbolizes the passage to the second step flow of communication. Sharing is therefore the circumstantial reification of personal influence which transforms the user-receiver into an opinion leader. In this 2.0 user-receiver model of the new media digital-social networks ecosystem, 2.0 opinion leaders can be compared to opinion sharers. 2.0 user-receivers are no longer only influenced by discussions led by opinion leaders within the groups to which they belong, but they are also influenced as soon as they receive information on social-digital networks by the filter operated by these same 2.0 opinion leaders. By mobilizing European and North American scientific literature, we wish to show the relevance of a canonical theoretical framework for the analysis of the uses and practices of social-digital networks through the prism of the reception of information from young adults. The goal of our approach is to link information (which is diffused by the media) to the communication of information (by users-receivers). In order to understand the situations of opinion influence at work in circulation and reception activities, the information filter processes will be studied by taking up the structural elements of the model proposed by the Columbia school ; in this model, those are the opinion leaders who are the real relays and filters of information. Our approach, both theoretically and methodologically, is a return to the original Columbia school literature. In accordance with this same literature, we aim to deploy an empirical social analysis steeped in both quantitative and qualitative methodology. We are interested in what "real people of everyday life" choose and do with media on social-digital networks, like the Columbia school which was interested in the people's choice and in particular in the part played by people in the flow of mass communications. The objective of this research is thus to transpose this Columbia model to the context of social-digital networks in order to update it and redefine, within it, the notion of opinion leader whose acceptance has been altered. Our contribution is therefore that of a social analysis of human communication of information via social-digital networks in the human and social sciences. [less ▲]

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See detailExploring the potential of citizen science for more adaptive and sustainable surface water governance in Luxembourg
Pickar, Karl Arthur UL

Doctoral thesis (2021)

The following Ph.D. thesis describes a research project, which aimed to explore the potential of environmental citizen science to contribute to more adaptive surface water governance in Luxembourg and ... [more ▼]

The following Ph.D. thesis describes a research project, which aimed to explore the potential of environmental citizen science to contribute to more adaptive surface water governance in Luxembourg and beyond. Citizen science projects are research projects, which are marked by the active engagement of members of the public. Adaptive governance refers to a type of governance, which is based on the engagement of diverse types of knowledge, perspectives, and stakeholders, and on building adaptive capacity in the face of unforeseen change and coordination across levels and scales. The research contributes to the conceptual development of citizen science in the context of adaptive governance and provides an example of a co-design process with a focus on building a citizen science tool for the exploration of social-ecological systems. In addition, the thesis contributes to practical development by identifying a set of opportunities for change of current data collection and meaning-making towards more adaptive surface water governance in Luxembourg and by making first experiences with surface water citizen science in Luxembourg, while engaging multiple place-based, regional, and national partners. Towards the above-mentioned goal, the research project, first, examined the current data collection programmes and meaning-making approaches for the governance of surface water bodies in Luxembourg. Prevailing practices are discussed based on key criteria for adaptive governance based on relevant academic literature. The research project, then, examined different approaches to environmental citizen science as alternative and complementary data collection programmes and meaning-making approaches in view of their potential to contribute to more adaptive surface water governance.The research project set out to do so by taking a transdisciplinary sustainability science research approach. The methodology encompassed (1) semi-structured qualitative interviews with specialists in the water domain and documentary review to gain insights into the current data collection programmes and meaning-making approaches in Luxembourg, (2) the trialling of two contributory surface water citizen science projects based on the Freshwater Watch citizen science tool by Earthwatch, an approach, in which volunteers are called upon to engage in data collection designed by scientists, and (3) the co-creation of surface water citizen science projects with interested groups based in Luxembourg centred around co-design workshops, in which the co-design partners were invited to explore changes and challenges and to develop sets of parameters for investigating the state of surface water bodies based on their research interests. In line with other studies, the findings show that citizen science can, indeed, constitute new sources of data on surface water bodies and, thus, increase data availability. Citizen science can lead to datasets on multiple temporal and spatial levels, and may increase overall transparency (of, for example, data on water quality). It can also contribute to more transparency in the meaning of data and increase the capacity for individual meaning-making. The findings show, in particular, that citizen science can increase the diversity of approaches to data collection and meaning-making, as projects constitute channels for the engagement of different knowledge types and can utilise new funding sources with alternative funding criteria. In addition, the case studies have shown that citizen science is particularly useful for complementing current official data collection, in particular, with respect to data from smaller water bodies, and for linking ecological data with social and technological data for a faster detection of changes in the system and a better grasp of the evolution of drivers of change. Interestingly, the study suggests that contributory citizen science may be better suited for the initial engagement of those, who are not specialised or professionally engaged in the water domain. Specialists and professionals, in turn, showed a bigger interest in engaging in co-design. [less ▲]

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See detailPolitical Philosophy
Heidemann, Dietmar UL

in Kant Yearbook (2021), 13

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See detailAuthenticity. Historical Data Integrity and the Layered Materiality of Digital Objects
Fickers, Andreas UL

in Balbi, Gabriele; Ribeiro, Nelson; Schafer, Valerie (Eds.) et al Digital Roots. Historicizing Media and Communication Concepts of the Digital Age (2021)

As media environments and communication practices evolve over time, so do theoretical concepts. This book analyzes some of the most well-known and fiercely discussed concepts of the digital age from a ... [more ▼]

As media environments and communication practices evolve over time, so do theoretical concepts. This book analyzes some of the most well-known and fiercely discussed concepts of the digital age from a historical perspective, showing how many of them have pre-digital roots and how they have changed and still are constantly changing in the digital era. Written by leading authors in media and communication studies, the chapters historicize 16 concepts that have become central in the digital media literature, focusing on three main areas. The first part, Technologies and Connections, historicises concepts like network, media convergence, multimedia, interactivity and artificial intelligence. The second one is related to Agency and Politics and explores global governance, datafication, fake news, echo chambers, digital media activism. The last one, Users and Practices, is finally devoted to telepresence, digital loneliness, amateurism, user generated content, fandom and authenticity. The book aims to shed light on how concepts emerge and are co-shaped, circulated, used and reappropriated in different contexts. It argues for the need for a conceptual media and communication history that will reveal new developments without concealing continuities and it demonstrates how the analogue/digital dichotomy is often a misleading one. [less ▲]

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See detailIntroduction: sémiotiques de l'archive
Fickers, Andreas UL; Dondero, Maria Guilia; Tore, Gian Maria UL et al

in Signata. Annales des Sémiotiques (2021), 12

Ce numéro de Signata vise à poser la question de l’archive d’un point de vue sémiotique et sémio-pragmatique. On entend ici par « sémiotique » non pas une discipline unique, mais une pluralité de manières ... [more ▼]

Ce numéro de Signata vise à poser la question de l’archive d’un point de vue sémiotique et sémio-pragmatique. On entend ici par « sémiotique » non pas une discipline unique, mais une pluralité de manières de questionner le sens, les formes et les valeurs au sein des disciplines historiques, sociologiques, philosophiques, linguistiques, médiatiques, artistiques, etc. Le but du dossier est ainsi la constitution d’une cartographie qui embrasse les différentes approches qui, dans le domaine de l’archive, peuvent faire émerger les questionnements liés au sens. [less ▲]

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See detailOn deformation quantization of quadratic Poisson structures
Merkoulov (merkulov), Serguei UL; Khoroshkin, Anton

E-print/Working paper (2021)

We study the deformation complex of the dg wheeled properad of Z-graded quadratic Poisson structures and prove that it is quasi-isomorphic to the even M. Kontsevich graph complex. As a first application ... [more ▼]

We study the deformation complex of the dg wheeled properad of Z-graded quadratic Poisson structures and prove that it is quasi-isomorphic to the even M. Kontsevich graph complex. As a first application we show that the Grothendieck-Teichmüller group acts on the genus completion of that wheeled properad faithfully and essentially transitively. As a second application we classify all universal quantizations of Z-graded quadratic Poisson structures together with the underlying (so called) homogeneous formality maps. [less ▲]

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See detailToken Economy
Sunyaev, Ali; Kannengießer, Niclas; Beck, Roman et al

in Business and Information Systems Engineering (2021)

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See detailThe Geostationary Ring: Practice and Law, Martha Mejia-Kaiser, Nijhoff/ Brill, Leiden 2020
Hofmann, Mahulena UL; Blount, Percy UL

in Air and Space Law (2021), 46(3), 475-478

The book is a comprehensive analysis of the international regime of the geostationary orbit.

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See detailCOVID19 Disease Map, a computational knowledge repository of virus-host interaction mechanisms.
Ostaszewski, Marek UL; Niarakis, Anna; Mazein, Alexander UL et al

in Molecular systems biology (2021), 17(10), 10387

We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS-CoV-2 infection, improving data interpretation and predicting key targets ... [more ▼]

We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS-CoV-2 infection, improving data interpretation and predicting key targets of intervention. Here, we describe a large-scale community effort to build an open access, interoperable and computable repository of COVID-19 molecular mechanisms. The COVID-19 Disease Map (C19DMap) is a graphical, interactive representation of disease-relevant molecular mechanisms linking many knowledge sources. Notably, it is a computational resource for graph-based analyses and disease modelling. To this end, we established a framework of tools, platforms and guidelines necessary for a multifaceted community of biocurators, domain experts, bioinformaticians and computational biologists. The diagrams of the C19DMap, curated from the literature, are integrated with relevant interaction and text mining databases. We demonstrate the application of network analysis and modelling approaches by concrete examples to highlight new testable hypotheses. This framework helps to find signatures of SARS-CoV-2 predisposition, treatment response or prioritisation of drug candidates. Such an approach may help deal with new waves of COVID-19 or similar pandemics in the long-term perspective. [less ▲]

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See detailQuantifying activities of daily living impairment in Parkinson’s disease using the Functional Activities Questionnaire
Becker, Sara; Pauly, Claire UL; Lawton, Michael et al

in Neurological Sciences (2021)

Objective Cognitive-driven activity of daily living (ADL) impairment in Parkinson’s disease (PD) is increasingly discussed as prodromal marker for dementia. Diagnostic properties of assessments for this ... [more ▼]

Objective Cognitive-driven activity of daily living (ADL) impairment in Parkinson’s disease (PD) is increasingly discussed as prodromal marker for dementia. Diagnostic properties of assessments for this specifc ADL impairment are sparsely investigated in PD. The ability of the Functional Activities Questionnaire (FAQ) for diferentiating between PD patients with normal cognition and with mild cognitive impairment (PD-MCI), according to informant and self-reports, was examined. Global cognitive function in groups with and without mild ADL impairment was compared according to diferent cut-ofs. Methods Multicenter data of 589 patients of an international cohort (CENTRE-PD) were analyzed. Analyses were run separately for informant-rated and self-rated FAQ. Receiver operating characteristic (ROC) analysis was conducted to defne the optimal FAQ cut-of for PD-MCI (≥1), and groups were additionally split according to reported FAQ cut-ofs for PD-MCI in the literature (≥3,≥5). Binary logistic regressions examined the efect of the Montreal Cognitive Assessment (MoCA) score in PD patients with and without mild ADL impairment. Results Two hundred and twenty-fve (38.2%) patients were classifed as PD-MCI. For all three cut-of values, sensitivity was moderate to low (<0.55), but specifcity was moderately high (>0.54) with a tendency of higher values for self-reported defcits. For the self-report, the cut-of≥3 showed a signifcant efect of the MoCA (B= −0.31, p=0.003), where FAQ≥3 patients had worse cognition. No efect for group diferences based on informant ratings was detected. Conclusion Our data argue that self-reported ADL impairments assessed by the FAQ show a relation to the severity of cognitive impairment in PD. [less ▲]

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See detailImportance of the biomass formulation for cancer metabolic modeling and drug prediction.
Moscardo Garcia, Maria UL; Pires Pacheco, Maria Irene UL; Bintener, Tamara Jean Rita UL et al

in iScience (2021), 24(10), 103110

Genome-scale metabolic reconstructions include all known biochemical reactions occurring in a cell. A typical application is the prediction of potential drug targets for cancer treatment. The precision of ... [more ▼]

Genome-scale metabolic reconstructions include all known biochemical reactions occurring in a cell. A typical application is the prediction of potential drug targets for cancer treatment. The precision of these predictions relies on the definition of the objective function. Generally, the biomass reaction is used to illustrate the growth capacity of a cancer cell. Today, seven human biomass reactions can be identified in published metabolic models. The impact of these differences on the metabolic model predictions has not been explored in detail. We explored this impact on cancer metabolic model predictions and showed that the metabolite composition and the associated coefficients had a large impact on the growth rate prediction accuracy, whereas gene essentiality predictions were mainly affected by the metabolite composition. Our results demonstrate the importance of defining a consensus biomass reaction compatible with most human models, which would contribute to ensuring the reproducibility and consistency of the results. [less ▲]

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See detailO'Dair, Marcus: Distributed Creativity
Smethurst, Reilly UL; Fridgen, Gilbert UL

in Zeitschrift für Urheber- und Medienrecht (2021), (11),

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See detailClimate Change and Pandemics: The Need for a Renewed EU Risk-Management Strategy
Donati, Alessandra UL

in Comparative Law Yearbook of International Business (2021)

Coronavirus and climate change are not two different crises. They represent two sides of the same significant turmoil relating to the progressive degradation of our environmental and health ecosystems ... [more ▼]

Coronavirus and climate change are not two different crises. They represent two sides of the same significant turmoil relating to the progressive degradation of our environmental and health ecosystems. Against this backdrop, and in light of, not only, the cyclical time of pandemics, but also of the predictable occurrence of a new pandemic associated with the worsening of the climate crisis, what should EU law do to prevent and better manage the occurrence of such risks? To answer this question, the core claim of this paper is that the EU should implement a common, coordinated, and consistent risk management strategy. [less ▲]

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See detailGeneration of two human induced pluripotent stem cell lines from fibroblasts of unrelated Parkinson’s patients carrying the G2019S mutation in the LRRK2 gene (LCSBi005, LCSBi006)
Novak, Gabriela; Finkbeiner, Steven; Skibinski, Gaia et al

in Stem Cell Research (2021), 57

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See detailWhat You See is What it Means! Semantic Representation Learning of Code based on Visualization
Keller, Patrick UL; Kabore, Abdoul Kader UL; Plein, Laura et al

in ACM Transactions on Software Engineering and Methodology (2021)

Recent successes in training word embeddings for NLP tasks have encouraged a wave of research on representation learning for sourcecode, which builds on similar NLP methods. The overall objective is then ... [more ▼]

Recent successes in training word embeddings for NLP tasks have encouraged a wave of research on representation learning for sourcecode, which builds on similar NLP methods. The overall objective is then to produce code embeddings that capture the maximumof program semantics. State-of-the-art approaches invariably rely on a syntactic representation (i.e., raw lexical tokens, abstractsyntax trees, or intermediate representation tokens) to generate embeddings, which are criticized in the literature as non-robustor non-generalizable. In this work, we investigate a novel embedding approach based on the intuition that source code has visualpatterns of semantics. We further use these patterns to address the outstanding challenge of identifying semantic code clones. Wepropose theWySiWiM(“What You See Is What It Means”) approach where visual representations of source code are fed into powerfulpre-trained image classification neural networks from the field of computer vision to benefit from the practical advantages of transferlearning. We evaluate the proposed embedding approach on the task of vulnerable code prediction in source code and on two variationsof the task of semantic code clone identification: code clone detection (a binary classification problem), and code classification (amulti-classification problem). We show with experiments on the BigCloneBench (Java), Open Judge (C) that although simple, ourWySiWiMapproach performs as effectively as state of the art approaches such as ASTNN or TBCNN. We also showed with datafrom NVD and SARD thatWySiWiMrepresentation can be used to learn a vulnerable code detector with reasonable performance(accuracy∼90%). We further explore the influence of different steps in our approach, such as the choice of visual representations or theclassification algorithm, to eventually discuss the promises and limitations of this research direction. [less ▲]

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